Diagnosis of antiphospholipid syndrome in routine clinical practice

• Published in: Lupus Vol. 22; no. 1; pp. 18 - 25
• Main Authors: Gardiner, C, Hills, J, Machin, SJ, Cohen, H
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.01.2013; Sage Publications Ltd
• Subjects: Antibodies; Antibodies, Anticardiolipin - blood; Anticoagulants; antiphospholipid antibodies; antiphospholipid syndrome; Antiphospholipid Syndrome - blood; Antiphospholipid Syndrome - diagnosis; Antiphospholipid Syndrome - immunology; beta 2-Glycoprotein I - immunology; Biomarkers - blood; cardiolipin; Clinical medicine; Clinics; Data processing; Female; Gynecology; Humans; Immunoglobulin G; Immunoglobulin M; Linear Models; Lupus; Lupus Coagulation Inhibitor - blood; Male; Morbidity; Obstetrics; Predictive Value of Tests; Pregnancy; Pregnancy Complications - blood; Pregnancy Complications - diagnosis; Pregnancy Complications - immunology; Retrospective Studies; Serology; Systematic review; Thrombosis; Thrombosis - blood; Thrombosis - diagnosis; Thrombosis - immunology; United Kingdom > UK
• ISSN: 0961-2033; 1477-0962
• DOI: 10.1177/0961203312460722

The updated international consensus criteria for definite antiphospholipid syndrome (APS) are useful for scientific clinical studies. However, there remains a need for diagnostic criteria for routine clinical use. We audited the results of routine antiphospholipid antibodies (aPLs) in a cohort of 193 consecutive patients with aPL positivity-based testing for lupus anticoagulant (LA), IgG and IgM anticardiolipin (aCL) and anti-ß2glycoprotein-1 antibodies (aß2GPI). Medium/high-titre aCL/aβ2GPI was defined as >99th percentile. Low-titre aCL/aβ2GPI positivity (>95th < 99th percentile) was considered positive for obstetric but not for thrombotic APS. One hundred of the 145 patients fulfilled both clinical and laboratory criteria for definite APS. Twenty-six women with purely obstetric APS had persistent low-titre aCL and/or aβ2GPI. With the inclusion of these patients, 126 of the 145 patients were considered to have APS. Sixty-seven out of 126 patients were LA-negative, of whom 12 had aCL only, 37 had aβ2GPI only and 18 positive were for both. The omission of aCL or aβ2GPI testing from investigation of APS would have led to a failure to diagnose APS in 9.5% and 29.4% of patients, respectively. Our data suggest that LA, aCL and aβ2GPI testing are all required for the accurate diagnosis of APS and that low-titre antibodies should be included in the diagnosis of obstetric APS.